The current frequency filings [Compass ITU Filing] [1] for radio bands made by China to the International Telecommunications Union (ITU) indicate that it would overlay both the Galileo Public Regulated Service (PRS) and the military GPS M-code at E1/L1, as well as in the L2 band. Given the importance of these protected signals and bands, we describe next in detail the intended signal plan of BeiDou. Since the use that China plans to do with BeiDou is still unclear, the spectra will be plotted in the next figures in grey to underline this fact.

Contents

BeiDou B1 Band

Although not all the technical aspects of the BeiDou signals in B1 are defined yet, an envisaged signal waveform has already been submitted to the ITU [Compass ITU Filing] [1]. Next figure shows the spectral details of the studied option in the B1 and B1-2 bands.

Figure 1: Spectra of BeiDou Signals in B1 bands

As also done in previous chapters, in order to have a better overview of all the GNSS signals around the BeiDou B1 band, next figure depicts the spectral environment:

It is important to note that the GPS L1C pilot and data signals are shown in quadrature in the figure although according to [GPS ICD-800][2] the final phasing is still to be decided. To conclude some technical characteristics of the BeiDou B1 signals are given next:

BeiDou B2 Band

Similar to the B1 band, not all the technical aspects of the BeiDou signals in B2 have been defined yet. Nonetheless a proposed signal waveform has already been submitted to the ITU [Compass ITU Filing] [1]. Next figure shows the spectral details of the studied option.

Figure 3: Spectra of BeiDou Signals in the B2 band.

As also done for the rest of GNSS bands, we show in the next figure all the systems together.

Figure 4: Spectra of Galileo and BeiDou signals in the E5 - B2 bands.

To conclude, some technical characteristics on the BeiDou B2 signals are presented more in detail in the next table:

BeiDou B3 Band

Finally, the spectral characteristics of the BeiDou B3 signals are also shown here. Similar to the B1 and B2 bands, not all the technical aspects of the BeiDou signals are defined yet. Next figure shows the Power Spectral densities of the proposed BeiDou signals in B3:

Figure 5: Spectra of BeiDou Signals in the E6 - B3 band.

In order to have a better insight on how the Galileo E6 – BeiDou B3 band looks like, the following figure presents all the planned signals together.

Figure 6: Spectra of Galileo and BeiDou Signals in the E6 - B3 band.

To conclude, some technical characteristics on the BeiDou B3 signals are provided next [Compass ITU Filing] [1].

Credits

The information presented in this NAVIPEDIA’s article is an extract of the PhD work performed by Dr. Jose Ángel Ávila Rodríguez in the FAF University of Munich as part of his Doctoral Thesis “On Generalized Signal Waveforms for Satellite Navigation” presented in June 2008, Munich (Germany)